Nested Binding Sources and DataGridView

[JaedenRuiner]

Simple Setup:

class MyObject {
public string Name {get;set;}
public BindingList<ChildObject> Children {get;set;}
}

BindingList<MyOjbect> blist1;

BindingSource bs1;
BindingSource bs2;
ComboBox cb;
DataGridView dgv;


class Form1 : Form {

override OnShown() {
bs1.DataSource = blist1;
cb.DataSource = bs1;
cb.DisplayMameber = "Name";

// this does not show the actual data in the dgv.
bs2.DataSource = bs1;
bs2.DataMember = "Children"

dgv.DataSource = bs2;
}

// using this event system works
void bs1_CurrentChanged() {
dgv.DataSource = bs1.Current;
dgv.DataMember = "Children";
}

}

so, quite obviously a pseudo code here, but simply a simple nested collection of objects, (using BindingList for ease of binding). A form with a combobox, datagridview, and two bindingsources objects. If I assign the bs2 binding source to use the first bindingsource as its data source, the data grid view will show 10 rows or 4 rows, etc, but all the databound defined columns will be blank, as if there is no data. I can even trap the "row select" event for the datagrid view, and the Row.DataBoundItem is Accurate, but the data is not being visual displayed by the grid.

However, if I instead trap the "currentchanged" event of the binding source, I can assign the "Current" to the datagridview data source, assign the DataMember and suddenly i get the data displayed in the grid.

This behavior is very strange. Why is it not working as nested binding sources?

Thanks

Jaeden "Sifo Dyas" alRaec Ruiner


"Never Trust a computer. Your brain is smarter than any micro-chip."
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